#loading {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    z-index: 15000;
}

#loading img {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 50px;
    height: 50px;
    margin-top: -25px;
    margin-left: -25px;
}